Methodrof manufacturing horseshoe nails



(No Model.)

W. W. MINER. METHOD OF MANUFACTURING HORSESHOE NAILS.

No. 490,394. Patented Jan. 24, 1893.

Fries.

ATEN'I WILLIAM IV. MINER, OF NEW HAVEN, ASSIGNOR TO THE NEW PROCESS NAILCOMPANY, OF TORRINGTON, CONNECTICUT.

METHODiOF MANUFACTURING HORSESHOE NAILS.

SPECIFICATION forming part of Letters Patent No. 490,394, dated January24, 1893.

Application filed May 26, 1892. Serial No. 434,490. (No model.)

To all whom it may concern.-

Be it known that I, WILLIAM W. MINER, of New Haven,in the county of NewHaven and State of Connecticut, have invented certain new and usefulImprovements in Methods of Manufacturing Horseshoe-Nails; and I dohereby declare the following to be a full, clear, and exact descriptionof the invention, such as will enable others skilled in the art to whichit appertains to make and use the same.

My invention relates to an improved method of manufacturing horse-shoenails.

The object of the invention is to produce horse-shoe nails perfectlyhomogeneous in structure; not liable to split or sliver; s'ufficientlystiff and hard to be driven without buckling, and soft and ductileenough to be easily clinched, and with smooth and rounded corners and ahighly finished surface.

WVith these ends in View my invention consists in the method ofmanufacturing horseshoe nails as will be hereinafter described andpointed out in the claim.

In the accompanying drawings Figure 1 represents a coil of wire the endof which has been reduced by suitable machinery to form the shank andhead of a horse-shoe nail. Fig. 2 is a detached view representing a Viewin section of the swaging dies for reducing the shank and head. Fig. 3is a view of the blank. Figs. 4. and 5 are side and edge views of thecompleted nail.

In manufacturing horse-shoe nails by my improved process I take a coilof rounded wire, preferably of Siemens & Mart-ins steel, and place it ona reel from which it is automatically fed to a suitable wire-pointingmachine and for this purpose I may use the well known I-Iopson 85 Brooksor the Dayton wire pointing machines, it being understood of course thatin the use of either one of these machines or of any other the dieswould re quire such modification in shape and size as would adapt themfor use in the manufacture of horse-shoe nails. The end of the coil ofwire is fed into the wire pointing machine and is reduced to the formshown in Fig. 1.

I have illustrated in Fig. 2 a vertical section of the dies and the formimparted to the end of the wire.

A A represent the swaging dies which being carried within a rapidlyrotating head serve to impart a great number of blows to every portionof the surface of the wire and reduce it to a tapering form circular incross section from the shoulder a to the point I). The supplemental diesB B operate upon that portion of the wire adjacent to the shank, and bytheir repeated blows serve to impart thereto a head C which is circularin cross-section. The blank after having been thus reduced by swaging tothe form shown in Fig. 2, is withdrawn from the dies and severed fromthe coil-which operation may be effected automatically by any suitablecutter whereby there is produced the blank shown in Fig. 3, in which Crepresents the head having a flat top 0. The head is gradually enlargedfrom its fiat top 0 to the point of its greatest diameter which isrepresented at d and from the latter point the head is gradually reducedin diam eter and merges into the tapering shank.

The operation of reducing the blank by swaging renders it exceedinglyhard and homogeneous in its structure and imparts to every portion ofits surface, a smooth and highly polished finish. In order to soften themetal sufficiently to enable the nail to be readily clinched I prefer toanneal the blanks at this stage and one suitable method of annealing isas follows. The blanks are placed in a muffle from which air is expelledby the introduction of illuminating gas under pressure. The muffle isthen placed in a suitable furnace and heated to a temperature sufficientto impart a cherry red heat to the blanks when it is removed and allowedto cool gradually and when the blanks are sufficiently cool they areremoved from the mufiile. By their being subjected to an annealingprocess, the blanks are rendered quite soft and ductile and owing to theexclusion of air from the muffie I prevent the oxidation of the surfaceof the blanks and preserve to them their brightly polished surfaceproduced in the process of swaging, while by gradually cooling theblanks I prevent the color from flowing. The blanks are then subjectedto a pressing process by which they are flattened on their oppositesides as represented in Figs. 4 and 5.

This step in the process may be performed by machinery of the generalcharacter set forth in Letters Patent No. 415,818 granted to me November26, 1889, or any othersuitable machinery or devices may be used for thispurpose. The flattenin g of the blank operates to transform it into theshape of a completed nail having flattened sides cl (1 rounded edges e ebeveled pointf and flat top The entire surface of the nail is renderedperfectly smooth and has imparted thereto a highly finished appearance.

The final operation of pressing by which the blank is flattened and itspointis beveled operates to impart to the annealed blank the requisitedegree of hardness and stiffness to the shank and point to insure thenail being driven Without bending or buckling While on the other handthe nail is suffieiently soft and ductile to be easily clinched.

It will be observed that by my improved process, I produce the head andshank of the nail by swaging and hence every portion of the nail issubstantially equal in hardness and is homogeneous throughout. BysWaging the upper end of the head, I not onlyimpart the desired form tothe head of the nail, but also point the end of the Wire so that whenthe swaged blank is severed therefrom the end of the wire is in acondition to be again fed to the swaging dies.

I do not restrict myself to the employment of any special form ofswaging machines or pressing dies, as it is evident that my improvedprocess may be carried into eiitect on Widely varying forms andconstructions of machines.

Having fully described my invention What I claim as new and desire tosecure by Letters Patent is:-

The method of making horse-shoe nails which consists in reducing the endof a Wire coil or length of Wire by swaging and forming a blankconsisting of a head circular in cross-section and a tapering shankcircular in cross-section throughout its length; severing the blank fromthe coil or length of Wire, annealing the blank and then flattening thehead and shank of the blank and thereby producing a nail havingflattened sides and rounded edges throughout its length.

In testimony whereof I have signed. this specification in the presenceof two subscribing witnesses.

WILLIAM W. MINER.

Witnesses:

S. G. NOTTINGHAM, O. S. DRURY.

